Security Analysis of AES Using Functionality Fault Model

Security of cryptographic circuits is a major concern. Smartcards are targeted by sophisticated attacks like fault attacks that combine physical disturbance and cryptanalysis. We propose a methodology and a tool (PAFI) to analyse the robustness of circuits under fault attacks using fault injection in simulation. The number of injection is reduced by taking into account the function of the latches in the whole circuit. We tested a circuit implementing the cryptosystem AES and showed that our approach reduces the number of fault injections to be performed (-80%). Moreover, most of the selected injection points are the ones that lead to known fault attacks (95%).